1. Field of the Invention
The present invention relates to digital networks and the handling of information traffic therein. More particularly, the invention concerns the provision of differentiated quality of service (QoS) levels for data exchanged between endpoints in an Internet Protocol (IP) network.
2. Description of the Prior Art
By way of background, various QoS mechanisms have been implemented to provide prioritized data transmission service in modern IP networks. Instead of using a “best effort” communication mode that treats all data the same, these QoS mechanisms prioritize network traffic into differentiated service categories. High priority traffic categories may thus be defined (e.g., voice communications, video/audio streams, etc.) and processed at a higher priority than other network data, thereby reducing undesirable network transmission problems such as dropped packets, latency, jitter, etc. Well known QoS mechanisms include the link level traffic prioritization scheme defined by the IEEE (Institute of Electrical and Electronics Engineers) 802.1p standard and the network level prioritization schemes implemented by RSVP (ReSource reserVation Procotol) and DiffServ (Differentiated Service).
Although the foregoing QoS mechanisms work well for transporting data across routing nodes within an IP network, bottlenecks can develop at network endpoints when the endpoint systems are unable to process the packets they receive in a timely fashion. This can occur, for example, when device/system queues are full, memory is low, processing resources are overburdened, etc. As a result, high priority packets can be dropped or blocked behind normal or low priority packets, thus defeating the purpose of the QoS scheme.
Accordingly, a need exists for an improvement in the provision of network QoS such that bottlenecks associated with network endpoints can be reduced or eliminated. What is required is a technique that allows incoming high priority packets to be handled efficiently and with due regard being given to their QoS priority level.